Controversial New Idea: Nerves Transmit Sound, Not Electricity

Nerves transmit sound waves through your body, not electrical pulses, according to a controversial new study that tries to explain the longstanding mystery of how anesthetics work. Textbooks say nerves use electrical impulses to transmit signals from the brain to the point of action, be it to wag a finger or blink an eye.

"But for us as physicists, this cannot be the explanation," says Thomas Heimburg, a Copenhagen University researcher whose expertise is in the intersection of biology and physics. "The physical laws of thermodynamics tell us that electrical impulses must produce heat as they travel along the nerve, but experiments find that no such heat is produced."